In-depth strategy
Prism Cascade: Plan the Second Clear, Not Just the First
Prism Cascade combines seven tetromino shapes with six colours on a 10×20 board. A connected orthogonal group of five or more matching cells clears, gravity compresses each column, and the game checks again for another group. The best move is therefore the one that improves both the current surface and the board that gravity will reveal.
Game facts used in this guide
- ✓10 columns by 20 rows
- ✓Groups require at least five orthogonally connected cells
- ✓Cascade bonus adds 50 points for each clear after the first, before the level multiplier
- ✓Level rises after every 15 cleared cells and falling speed increases
Read colours and shape separately
Every falling piece has a tetromino shape and one colour. First decide where the shape can land without creating a deep hole; then decide which landing helps that colour connect. Reversing that order often creates an attractive match above an unusable cavity.
The next-piece preview lets you reserve a surface for the coming shape. If an I piece is next, preserve a straight lane. If an O piece is next, avoid leaving a single-cell notch that it cannot fill.
Build four-cell invitations
A group of four does not clear, which makes it a useful prepared target. Place four connected cells where several future shapes can supply the fifth cell. A compact L-shaped group is usually more flexible than a one-cell-wide vertical tower.
Do not build several isolated groups of the same colour across the board. Gravity only moves cells downward within their columns; it does not pull columns sideways. Groups must have a realistic way to become adjacent.
Plan the board after gravity
When the first group disappears, every cell above it falls. Before locking a piece, trace which colours will touch after that fall. A true cascade setup has a specific second connection; hoping that colours happen to meet is not a plan.
Example: a five-cell purple group supporting two separated yellow clusters can be valuable if removing purple drops the upper yellow cluster directly onto the lower one. The second clear then earns the combo bonus automatically.
Keep the skyline recoverable
A low board is helpful, but an even board is not always best. Shallow steps give J, L, S and Z pieces places to settle. Deep one-cell wells and tall isolated towers are dangerous because only a small part of the piece set can repair them.
Use quiet turns to flatten a dangerous peak or fill a cavity. Scoring zero on one placement can be correct when it preserves many valid landings for the next three pieces.
Controls, speed and emergency thinking
On desktop, move, rotate, soft-drop and hard-drop are separate actions. On touch, horizontal swipes move, a slow downward swipe soft-drops, a fast downward swipe hard-drops and a double-tap rotates. Hard-drop only after checking the ghost landing.
As levels rise, spend less time improvising near the top. Decide the target column while the piece is high. If the top three rows become occupied, the run is already in a recovery phase: prioritise clearing height over building a perfect combo.